Arrangement for working the peripheral surfaces of grinding disks and the like



June 6, 193 9 E. BRlNKMANN :1 AL 2,161,609

, ARRANGEMENT FOR WORKLNG THE PERIPHERAL SURFACES 1 ,OF GRINDING DISKS AND THE LIKE v Fill d-Dec. 12, L936 2 Sheets-Sheet, 1

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E. BRINKMANN ET AL 2,161,509 MENT FOR WORKING THE 'PERIPHERAL SURFACES 7 OF GRINDING DISKS AND THE LIKE Filed D90. 12, 1936 ARRANGE 2 Sheets-Sheet 2 IwAl. DBR/N/(MA n/A/ ,BHV A l/L ARA/1N6 Patented June 6, 1939 UNITED STATES PATENT oFFlca 2,161,609 ARRANGEMENT roa WORKING 'ma ra- RIPHERAL SURFACES F DISKS AND THE LIKE GRINDING Ewald Brinkmann, Villigst, near Schwerte, and

Paul Arning, Iserlohn, Germany Application December 12, 1936, Serial No. 115,506 In Germany December 18, 1935 7 Claims. (Cl. 125-11) starting from the edge of the grindstone andworking towards the centre of the grindstone. The rolling tool is carried by a special holder which is pivotally mounted and longitudinally dis- 10 placeable in a carriage sliding transversely to the grindstone. This tool holder has two bores arranged at an angle to one another and which are each inclined at a suitable angle to the axis or peripheral surface of the grindstone, so that by inserting the tool in one or the other bore as well as by turning the tool holder through 180 the tool can be brought successively into four definite different pos tions. Arrangements are also known which relate primarily to the removal 0 and ready attachment of the above described device to grinding machines in such manner that the rolling tool is rigidly mounted by means of yokes and clamping screws, the device being secured to the grinding machine, its protecting 25 cover or some other machine element by means of yokes, clamps or the like. In contradistinction to these known arrangements, the present invention relates to a novel device for dressing or truing grindstones and the like in which two tool holdersmovable for simultaneous adjustment with respect to one another are mounted on a movable carriage, the rolling tools operating on the cylindrical peripheries of grinding disks or the like starting from, the'outer i5 edges and working towards the middle. In the embodiment illustrated and described in detail below, the tool holders and the means for adjusting these holders relatively to each other are so constructed and arranged that the rolling tools 40 and even their holders can pass each other freely, thus enabling the central or middle portion of the grinding disk or the like to be dressed or trued efflciently without any danger of a' clash between the two tools or their holders. The tool f holders are guided by means of rack bars constituting slides which can be moved positively and simultaneously with respectto one another in parallel directions at the same speed by means s of a pinion gear. This pinion gear is driven by means of a hand-wheel and worm gearing. The carriage can be moved towards the centre of the disk, that is to say, in a direction radial with respect to the disk. The guides and inner parts of 5; the carriage are enclosed in a dust tight 'manner by means of bands, such as steel bands, which participate in the movement of the slides.

The working spindle is arranged to be axially displaceable for adjustment to the two tools. The grinding disk is so mounted that the centre of its 5 thickness coincides with the centre position of the two rolling tools, thus insuring that the rolling tools will engage the two faces of the grinding disk simultaneously, The rolling tools are located at the same angle to the working spindle 10 l but by means of a ball joint the angle of cutting can be adjusted in accordance with the diameter of the grinding disk.

. A further advantage is obtained by providing a threaded engagement of the tool holders in 1 their mounts because by a small rotation of the tool holders in their mounts the two tool edges can be adjusted to precisely the same disk diameter. In comparison with the arrangements hitherto known the grinding disks can be clamped by means of the axially displaceable working spindle in a fraction of thetime hitherto required. 1 As the device is closed by means of bands participating in the movement of the tool-carrying slides, the wear is reduced to practically zero.

One embodiment-of the invention is shown by way of example in the accompanying drawings, in which Fig. 1 is an elevation of our improved machine, with parts in section; Fig. 2 is a detail view, with parts in section, looking inthe same direction as in Fig. 1, and showing, upon an .enlarged scale, only the grinding disk, the tool carriage, and the elements associated therewith; Fig. 2a is a horizontal section substantially on line 2a2a of Fig. 2; and Fig. 3 is a detail section, 5

upon a still larger scale, of one of the tools and the associatedelements. The grinding disk'l which is to be worked is'clamped between the disks 2 and 3. The disk! is driven by means of a the working spindle 3a which is axially dis- 40 placeable, the drive being transmitted by way of the bevel gears l, 5 from the driving shaft 6 and the pulley l. The'spindle 3a slides in the gear 5, but is held to rotate therewith. The disk 3 is provided with the centering pin 8 and is not a driven directly. The said disk can be moved axially by means of the hand-wheel 9, the worm Hi, the worm wheel II, the pinion I2 and the rack bar I3. The disk 3 is mounted to rotate upon an axle g, a ball bearing being indicated at f. The said axle is slidable vertically in a stationary pillar i. To guide the axle in this movement,

it is shown as provided with a longitudinal groove 0' into which fits a stationary key h. The rack bar Ii is integral with, or formed upon, the axle a, 56

and meshes with the pinion I2, the latter and the worm wheel ll being connected rigidly-so as to rotate in unison; for instance, the parts I l and I2 may both be secured rigidly to the shaft It. When the disk 3 is moved upwardly by the mechanism just described, to press the grinding disk I against the upper clamping disk 2, no accidental downward movement of the lower clamping disk 3 can take place, the worm l and worm wheel ll constituting a self-locking connection. The axial displacement of the working shaft 3a is effected by means of the worm l4 and the internally threaded worm wheel l5. The internal screwthread on the worm wheel l5 engages a mating external screwthread on a sleeve b, as indicated at 0. By means of ball bearings a, the

taut by means suchas shaft or spindle 3a is journaled in the sleeve b. This sleeve is movable longitudinally, but held against rotation, as by means of a stationary screw e projecting into a longitudinal groove d on said sleeve. The shaft So has a shoulder or other suitable formation so that downward movement of the sleeve b will force said shaft and the upper clamping disk 2 toward the grinding disk I. Accidental vertical movement of the shaft 3a and the disk 2 can not take place, being prevented by the self-locking character of the worm and worm wheel connection at I4, l5, and also by the self-locking character of the screwthreaded connection of the parts [5 and b at c.

Disposed on the carriage I6, which is shown in section in Figure 2, are the tool holders I! with the rolling tools l8. By means of the ball joints l9, shown in greater detail in Figure 3, the two cutting angles 20 (Fig. 2) and 2| (Fig. 2a) are adjusted. The tools are always at the same angle 22 to the working spindle, Figure 20.. As shown in Figures 2 and 2a, the ball joints l9 are secured to the vertically movable slides 24 by means of bolts 23. These slides are each provided with a rack bar 25 and are moved along parallel paths in opposite directions by means of the handwheel 26, worm 21, worm wheel 28 and pinion 29. The guides of the slides 24 and the interior of the carriage it are completely protected against dust by means of the steel bands 30 which participate in the movement of the slides; for instance, the bolts 23 may extend through said bands with a tight fit. Each band can be kept .threaded opening in the ball member l9 so that by.a small rotation of the holder I 1 in its support the tool I! on such holder can be moved in or out with respect to the member [9, and by turning the two holders l1, both tools can be adjusted to exactly the same disk diameter. The tool holder is secured'in position by means of the pressure member 31 and the clamping screw 38.

It will be noted that the two slides 24 and the parts carried thereby are not in axial alignment,

- but move in separate, parallel paths so arranged .that the two tools I! and even their holders l1 and carrier balls I9 can movepast each other without interference. This enables us to dress the middle portion of the periphery of the grindguide roller 3| and spring ing disk I just as effectively as the other portions to the mounted grinding disk and provided with parallel guides ranging lengthwise of said axis, two tool holders movable lengthwise of said guides, means for imparting simultaneous movement to said holders in opposite directions, and a rolling tool carried by each of said tool holders, adapted to engage the edge of the peripheral surface of the grinding disk and to move towards the centre thereof.

2. An arrangement for working thecylindrical surface of a grinding disk, comprising means for mounting the grinding disk and rotating it about its axis, a carriage movable radially with respect to the mounted grinding disk, two rack bars slidable in parallel guides on said carriage, means engaging said rack bars for imparting simultaneous and opposite movement thereto, a tool holder supported on each of said rack bars and a rolling tool carried by each of said tool holders, adapatedto engage the edge of the peripheral surface of the grinding disk and to move towards the centre thereof.

3. An arrangement for working the cylindrical surface of a grinding disk, comprising means for mounting the grinding disk and rotating it about its axis, a carriage movable radially with respect to the mounted grinding disk, two rack bars slidable in parallel guides on said carriage, means engaging said rack bars for imparting simultaneous and opposite movement thereto, bands attached to and participating in the movement of said rack bars to prevent the ingress of dust to said parallel'guides, a tool holder supported on each of said rack bars and a rolling tool carried by each of said tool holders, adapted to engage the edge of the peripheral surface of the grinding disk and to move towards the centre thereof.

4. A machine for dressing grinding disks and like implements, comprising means for rotating such implement about its axis, a carrier, two tool holder supports movable on said carrier in directions lengthwise-of said axis, each of said supports having a portion formed as a cup of a ball joint, a ball seated in each of said cups and provided with an extension having a threaded bore, two tool holders each provided with a stem threaded to fit said bore, clamping means for preventing accidental movement of the threaded stern in the threaded bore, a dressing tool mounted on each holder, and means for moving said tool holders simultaneously in opposite directions relatively to said carrier.

5. An arrangement for working the peripheral surface of a grinding wheel, including a main frame, a shaftaxially displaceable insaid frame, means for driving said shaft, a sleeve in which said shaft is rotatable, said sleeve being held to move axially in unison with the shaft but held against rotation and provided with an external thread, a member held against movement in the axial direction of said shaft and in threaded engagement with said threaded sleeve, means for rotating said member to eifect axial movement of the shaft, a clamping disk secured at one end of.s aid shaft, amember in alignment with said for moving said second member and second clamping disk towards and away from the first clamping disk, a centre pin on said second clamping disk, a carriage slidable on said main frame radially to said shaft, means for positively shifting said carriage on its slideway, two slides'movable on said carriage in a direction parallel to said shaft, a rack bar formed on each slide, a pinion engaging both rack bars for imparting 1o simultaneous and apposite movement to said slides, means for actuating said pinion, a tool holder adjustably supported on each slide and a rolling tool carried by each tool holder.

6. A machine for dressing grinding disks and 15 like implements, comprising means for rotatin such implement about its axis, a carriage movable toward and from said axis, two tool holders movable on said carriage in directions lengthwise of said axis, means for moving said tool holders simultaneously in opposite directions relatively to said carriage, and dressing tools carried by said holders.

7. A machine for dressing grinding disks and like implements, comprising means for rotating such implement about its axis, a support, two tool holders movable on said support along separate paths which extend lengthwise of said axis out of line with each other, so that said tool holders may pass each other, means for moving said tool holders simultaneously along said paths in opposite directions, and dressing tools carried by said holders.

YEWALD BRINKMANN. 7

PAUL ARNING. 

